NATIONAL WATER-QUALITY ASSESSMENT PROGRAM Yellowstone River Basin MAJOR WATER-QUALITY ISSUES IN WHAT IS THE NAWQA PROGRAM? THE YELLOWSTONE RIVER BASIN During the past 25 years, government and industry have made large financial investments aimed at improving water quality across the Nation. Major progress has been made; however, Assessing the water quality in the Yellowstone many water-quality issues remain. To address the need for consistent and scientifically sound River Basin is important for the protection and information for managing the Nation’s water resources, the U.S. Geological Survey began a utilization of the water resources. Changes in full-scale National Water-Quality Assessment (NAWQA) Program in 1991. The overall goals water quality can affect the entire ecosystem, of the NAWQA Program are to (1) describe current water-quality conditions for a large part raising concerns about drinking-water quality, of the Nation’s freshwater streams and aquifers, (2) describe how water quality is changing over time, and (3) improve our understanding of the primary natural and human factors habitat degradation or destruction, and loss of use affecting water quality. of the resource. The Yellowstone River Basin NAWQA study will increase the scientific understanding of surface- and ground-water quality and the factors that influence water quality. This information will benefit the water- resource managers that need, but often lack, the data to implement effective management actions and evaluate long-term changes in water quality. The Yellowstone River originates at the Continental Divide in Yellowstone National Park, Wyoming (photo of Lower Falls, Yellowstone Figure 1. Map showing Yellowstone River Basin NAWQA study unit. National Park, courtesy of Wyoming Assessing the quality of water in every location of the Nation would not be practical; Division of Tourism) therefore, NAWQA Program studies are planned within a set of areas called study units (fig. 1). These study units are composed of over 50 important river and aquifer systems that represent the diverse geography, water resources, and land and water uses of the Nation. The Major water-quality issues in the Yellowstone Yellowstone River Basin is one such study unit, designed to include the entire 70,100- River Basin vary from potential degradation of square-mile Yellowstone River drainage. Study activities by the U.S. Geological Survey in pristine streams in headwater areas to industrial the Yellowstone River Basin began in 1997. and agricultural effects in downstream reaches. The issues generally are related to effects of land elements also can be associated with • Sedimentation - Loss of streambank and water use, but some are related to natural suspended sediments in streams. vegetation, easily erodible soils, and many factors. land-use activities can contribute to • Trace elements - Leachate from mine spoils and • Toxic compounds - Potential sources for sediment problems in streams throughout tailings can increase trace elements in both toxic compounds in both ground water and the basin. ground water and streams. Leaching of soils streams include: leachate from abandoned derived from marine shales of Cretaceous age in and active landfills; pesticides and • Other related issues - Other potential some locations has caused high concentrations fertilizers from lawns and croplands; issues related to water quality in the basin of selenium in water resources. Geothermal hydrocarbons from leaking tanks, refining include: acidification of water resources by areas, like those in the Yellowstone National operations, pipelines, and spills; and waste leaching of mine spoils, nutrient Park area, can be sources of trace elements such from industrial and commercial activities. enrichment of ground water and streams as arsenic in both ground water and streams. from fertilizers and animal and human Because of the widespread distribution of • Salinity - Increases in the salinity of both waste, localized de-watering of sole-source uranium-bearing rocks, elevated ground water and streams can occur from aquifers, ground-water and stream quality concentrations of radon and other saline ground water disposal, irrigation related to coalbed methane production, radionuclides in water are a concern. Trace return flows, and some irrigation practices. and water-quality concerns on tribal lands. USGS Fact Sheet 149-97 1 Clarks Fork Yellowstone River valley. Mean Drainage area and mean annual streamflow for STUDY UNIT DESCRIPTION major tributary watersheds, Yellowstone River annual snowfall ranges from more than 130 The Yellowstone River basin study unit inches in Yellowstone National Park to about [Streamflow data through water year 1996; Note: mean annual extends from central Wyoming north to streamflow is from streamflow-gaging station near mouth of 16 inches in northeast Montana. respective river.] include most of southeastern Montana and a Rangeland is the dominant land use and small part of western North Dakota. The Drainage area land cover, with about 43 percent of the Mean annual entire Yellowstone River watershed defines Percent streamflow study unit composed of subhumid grassland the study unit boundaries and includes all of Square of study in cubic feet and semiarid grazing land. The remaining River miles unit per second the Wind/Bighorn, Powder, Tongue, and land uses and land cover include grazed and Clarks Fork 2,032 3 1,032 Clarks Fork Yellowstone tributary ungrazed forest (19%), grazed desert Yellowstone River watersheds. Total area for the study unit is shrubland (16%), mostly cropland and about 70,100 square miles (sq mi) of which Wind/Bighorn River 22,414 32 3,810 grazed cropland (non-irrigated: 11%; 51 percent is in Montana, 48 percent is in Tongue River 5,397 8 421 irrigated: 5%), grazed open woodland (5%), Wyoming, and 1 percent is in North Dakota. and alpine and lakes (1%). Powder River 13,189 19 586 Total population of the study unit was about 1 323,000 (1990 census), of which 206,000 Yellowstone River 69,103 99 12,750 were in Montana, 116,000 were in Wyoming, 1Includes Clarks Fork Yellowstone, Wind/Bighorn, and 1,000 were in North Dakota. Tongue, and Powder River Basins. The study unit lies within the Rocky Mountain System and Interior Plains addition to alluvial sources of ground water, physiographic divisions. Topography of the sandstone and coal beds within the Fort Union study unit in the Rocky Mountain System Formation of Tertiary age and sandstones in the division varies from mountain ranges and Fox Hills Formation of Upper Cretaceous age are high plateaus, including the Wind River important bedrock aquifers. The Wind River Range, Bighorn Mountains, and Absaroka Formation of Tertiary age is used to supply Plateau, to intermontane basins, such as the irrigation water in the Riverton, Wyoming area Wind River and Bighorn Basins. The highest Grazing by domestic livestock and other species with some wells yielding as much as elevations in the study unit are in the Wind on range and grasslands is a major land use in the 3,000 gallons per minute. Other aquifers in River Range, where several peaks exceed study unit (photo of North American Bison Mesozoic and Paleozoic units are productive but courtesy of Wyoming Division of Tourism) 13,000 feet above sea level. The Interior have not been extensively developed. Plains division part of the study unit varies from gently rolling plains to sharply Major land-use industries in the study unit About 98 percent of the total water used in the dissected badlands. The lowest point in the include coal and metals mining, oil and gas study unit in 1990 was surface water. Most of this study unit, 1,850 feet above sea level, is production, and agriculture. About 30 active water—about 99 percent—was used by the located at the mouth of the Yellowstone mines remove low-sulfur coal by surface agricultural industry for crops and livestock. River in North Dakota. strip-mining methods from the large coal However, ground water is an important resource reserves in the Tongue and Powder River in the study unit. About 97 percent of the Basins. Most of the metals mining occurs in domestic water supply and about 27 percent of the the mountainous regions of the study unit. public water supply is from ground water. About Oil and gas is produced from reservoirs in 62 percent of the total ground-water use in 1990 The Wind River flows the Powder River and Big Horn Basins. was for agricultural purposes. Public supply, north through the Much of the agricultural industry in the mining, power generation, and industry made up Wind River Canyon study unit is related to livestock production. most of the remaining uses of surface- and into the Bighorn ground-water in the study unit. Basin, where it The agricultural industry also includes becomes the Bighorn farming of irrigated cropland along alluvial River at the Wedding valleys and benches. Reported surface and ground water used by of the Waters (photo Drainage areas for the major tributary category in the Yellowstone River Basin, 19901 courtesy of Wyoming watersheds range from 22,414 sq mi for the Division of Tourism) [Note: category and total amounts expressed to two significant Wind/Bighorn River to about 2,032 sq mi for figures.] the Clarks Fork Yellowstone River. Mean annual flow ranges from 12,750 cubic feet Water used in millions of gallons per day per second (ft3/sec) for the Yellowstone Climate in the study unit ranges from cold Category Surface water Ground water River at Sidney Montana, to about 421 ft3/ and moist in the mountainous areas to sec for the Tongue River near the mouth. Public supply 40 15 temperate and semiarid in the plains areas. Streamflow in all the major watersheds is Domestic (self-supplied) .21 6.3 Annual temperature extremes range from affected by diversions. While there are no o Commercial .18 .25 about 30 degrees Fahrenheit ( F) below zero reservoirs on the mainstem Yellowstone o Industrial 16 1.5 during the winter to hotter than 100 F during River, several reservoirs regulate flow in the the summer.